[fix]|installexternal.py] Fix import of urllib.request
This changed to be the required way of importing the lib in some newer Python versions. https://docs.python.org/3.9/library/urllib.request.html and https://bugs.python.org/issue36701
This changed to be the required way of importing the lib in some newer Python versions. https://docs.python.org/3.9/library/urllib.request.html and https://bugs.python.org/issue36701